U.S. Pat. No. 4,625,633, in the name of Martin, is a commonly owned patent which describes a ventilated core unit for service connections. Various prior art patents are disclosed in the Martin patent. The disclosure of all of those prior art patents may be summarized by the statement in the Martin patent that none of the prior art disclose the benefits of an independently controllable zone unit that is not attached to the building HVAC equipment by air ducts.
Martin correctly identifies a modern trend in office furniture and layout arrangements, in which small, semiprivate working cubicles are created about a central core with multiple work stations and equipment emitting from that core. The Martin design has been very successful in providing a central core unit which accomplishes both ventilating and utility connections for peripheral work spaces.
The principal basis upon which the Martin invention is founded is the use of a central core unit for local ventilating and also for providing utility connections to peripheral work spaces around the core. The work spaces each are provided with electrical terminal devices and air inputs. A work space fan is mounted in a side wall of the cabinet. That fan is operable under user control to draw air from the work space into the plenum defined by the walls of the cabinet. The air is then discharged to the common area directly above the workspace.
No system is perfect, however, and several drawbacks have been encountered in the use of the Martin system. Specifically, the system is both assisted by and encumbered by the fact that it has a central column 30 which functions as a service conduit. This central core conduit makes it easy to supply power to the system. It also makes it significantly more difficult to remove the top 24 of the core for access to the internal mechanisms. In addition, mounting a filter 84 and fan 80 on the top 24 causes an imbalance unless the filter is centered. Of course, when a center conduit 30 is present, that cannot be accomplished. Alternatively, a plurality of fans 80 are required. In either case, difficulty in cleaning the filter 84 is significant because the center conduit is directly connected to top 24 of core unit 20.
Yet another difficulty which is experienced in prior art systems is that each core wall of core unit includes it own inlet fan which is adjustably controlled by the worker at each specific work station. This fan, however, does not directly control the exhaust air. A worker must be present in order to control the use of the specific intake fan for each wall of the core. In addition, of course, the requirement of a separate fan for each core wall increases expense and complicates the assembly and maintenance of the system.
Even though the Martin system is successful and provides many advantages to the users, that system is not capable of providing a complete, controlled environment which would be ideal under present day standards. Specifically, what is needed is a more efficient and effective way to transfer or treat the air within the region of all of the work stations about a central core workplace.
Ideally, the environment directly centered about the core of the stand alone work space should have the best possible environment. Particularly, bacteria and smoke should be eliminated and the individual work stations should each function in the nature of a cleanroom.
In addition, the device should be simple and easy to maintain. Access to the interior of the column for maintenance of other equipment should be facilitated and should not be prevented by the design of the air flow system. Greatly improved efficiencies and the ability to provide virtually an envelope of clean air are objects of the present invention and are not found in the prior art.